One of the biggest problems facing the European Union today is the fact that within its borders, 23 languages are spoken. This means that all the important documents have to be translated by a whole army of translators, which costs the taxpayer more than 1 billion Euros a year - and companies trading within the EU spend millions more. The EU-funded TC-STAR project aims to tackle this issue with technology: a system that eats speech in one language, and outputs that same speech in another.

It wouldn't work because of the well known nature of the nations in Europe.
If you pick English, German and French, Italians will require to be in too. If you let them in, Spain will claim Spanish is mandatory too. Then come the Polish noting they are equal in numbers to the Spaniards within the EU. And so on.